I’m surprised this would work anywhere. If you call “What” on the blue object, you can see it has edge tolerances of nearly one unit. You can also see how bad it is by exploding and rebuilding the edges. Please explain exactly how it was created so we can fix the problem in the creation code.

We are working on tests to detect bad geometry like this that can cause problems further down the line. We are also developing better feedback from boolean operations to indicate where and why failure occurs.